Yeah as others have noted it can take some dialing in. I had the same idea when I got started with a mummy style bag. The way I would suggest to use the mummy bag is to unzip it down to about your calves and once in your hammock put your feet in and pull it up over yourself like a blanket. This is how topquilts work. Not all hammocks stretch like that either. Get yourself an Eno double or if you wanna do it on the even less expensive, get a tableclothfactory.com crinkle tafetta table cloth and sew a channel on each end. There are some threads here on them. Underquilts provide a whole new level of comfort compared to pads. Don't give up, lot's of us have been there where you are know in regards to the frustration.
"He who makes a beast of himself, gets rid of the pain of being a man." Dr. Hunter S. Thompson
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